Frequency location indexing for a wideband component carrier

ABSTRACT

A method, system, and device for resource block (RB) indexing in a user equipment (UE) is provided. In an embodiment, the method includes obtaining, at the UE, a UE-independent frequency reference point. The method also includes determining, by the UE, a UE-independent index of an RB according to the UE-independent frequency reference point.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2017/088376, filed on Jun. 15, 2017. The disclosure of theaforementioned application is hereby incorporated by reference in itsentirety.

TECHNICAL FIELD

The present disclosure relates generally to a system and method forwireless communication, and, in particular embodiments, to a system andmethod for frequency location indexing for wideband component carrier.

BACKGROUND

5th generation mobile networks (5G) are the proposed next generation oftelecommunications standards beyond the current 4G standards. Some goalsof 5G include higher capacity than current 4G, thereby allowing a higherdensity of mobile broadband users. 5G also proposes to supportdevice-to-device, ultra-reliable, and massive machine communications.Additionally, 5G proposes to provide faster data transfer rates than arecurrently available. However, in order to achieve these goals, a numberof problems must be addressed and solved. One problem to overcome isproviding user equipment (UEs) with reference signals in a system inwhich the UE may not know the bandwidth of its component carrier (CC)and in a system that may include UEs that operate in intra-band carrieraggregation (CA) mode and UEs that operate in a single wideband mode.

SUMMARY

Technical advantages are generally achieved by embodiments of thisdisclosure which describe systems and methods for frequency locationindexing in a user equipment (UE) in wideband CC. An advantage of one ormore embodiments of the present disclosure is frequency locationindexing that is the same for all devices in a network regardless ofwhether the UE operates in a single normal CC mode, in intra-band CAmode or in a single wideband mode. Another advantage of one or moreembodiments of the present disclosure is that the frequency locationindexing may be performed without knowledge of the CC bandwidth. Otheradvantages will be apparent to those of ordinary skill in the art uponreading the disclosure below.

In accordance with an embodiment of the present disclosure, a method forresource block (RB) indexing in a user equipment (UE) includesobtaining, at the UE, a UE-independent frequency reference point. Themethod also includes determining, by the UE, a UE-independent index ofan RB according to the UE-independent frequency reference point.

In accordance with an embodiment of the present disclosure, a method forresource block (RB) indexing in a base station includes transmitting, toa user equipment (UE), a UE-independent frequency reference point. TheUE-independent frequency reference point is for determining aUE-independent index of an RB.

In accordance with an embodiment of the present disclosure, a userequipment (UE) includes a non-transitory memory storage comprisinginstructions and one or more processors in communication with thenon-transitory memory storage. The one or more processors executeinstructions for obtaining a UE-independent frequency reference point.The one or more processors also execute instructions for determining aUE-independent index of an RB according to the UE-independent frequencyreference point.

In accordance with an embodiment of the present disclosure, a basestation includes a non-transitory memory storage comprising instructionsand one or more processors in communication with the non-transitorymemory storage. The one or more processors execute instructions fortransmitting, to a user equipment (UE), a UE-independent frequencyreference point. The UE-independent frequency reference point is fordetermining a UE-independent index of an RB.

Optionally, in any of the preceding aspects, the reference point is alowest subcarrier of a lowest RB for a given numerology.

Optionally, in any of the preceding aspects, obtaining theUE-independent frequency reference point includes receiving an offsetsignaled in a remaining system information (RMSI). The offset isexpressed in terms of a number of RBs. Obtaining the UE-independentfrequency reference point also includes determining the UE-independentfrequency reference point from the offset.

Optionally, in any of the preceding aspects, the method also includesreceiving an SS block. The SS block is one of a plurality of SS blocks.The offset is from a lowest subcarrier of the SS block to theUE-independent frequency reference point.

Optionally, in any of the preceding aspects, the SS block of theplurality of SS blocks corresponds to the RMSI used for signaling theoffset.

Optionally, in any of the preceding aspects, the offset is from a centerfrequency of a carrier to the UE-independent frequency reference point.

Optionally, in any of the preceding aspects, the UE-independentfrequency reference point is a first frequency reference point and theUE-independent index is a first index. Before obtaining the firstfrequency reference point, the method further includes obtaining asecond frequency reference point. The method also further includesdetermining a second index of another RB according to the secondfrequency reference point, the another RB for decoding the RMSI or aCORESET of the RMSI.

The foregoing has outlined rather broadly the features of an embodimentof the present disclosure in order that the detailed description of thedisclosure that follows may be better understood. Additional featuresand advantages of embodiments of the disclosure will be describedhereinafter, which form the subject of the claims of the disclosure. Itshould be appreciated by those skilled in the art that the conceptionand specific embodiments disclosed may be readily utilized as a basisfor modifying or designing other structures or processes for carryingout the same purposes of the present disclosure. It should also berealized by those skilled in the art that such equivalent constructionsdo not depart from the spirit and scope of the disclosure as set forthin the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIG. 1 is a network diagram of a communication system;

FIG. 2A is a block diagram of an example electronic device;

FIG. 2B is a block diagram of an example electronic device;

FIG. 3 is a diagram of an embodiment of a WCC;

FIG. 4 is a diagram of an embodiment of a system of physical resourceblocks (PRBs) in the frequency domain;

FIGS. 5-10 are block diagrams each illustrating various options foridentifying the reference point as a location of a DL DC subcarrier ofWCC with reference to a common BWP;

FIG. 11 is a diagram of an embodiment of a system of subcarriers in thefrequency domain showing fixed uniform distance between consecutive SSblocks in a WCC;

FIG. 12 is a diagram of an embodiment of a system of subcarriers in thefrequency domain showing fixed uniform distance between consecutive SSblocks in a WCC;

FIG. 13 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-1 for SCS 2f₀ and 4f₀;

FIG. 14 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=2^(n) for SCS 0.5f₀ and option Alt (ii)-2 for SCS 2f₀ and 4f₀;

FIG. 15 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=2^(n) for SCS 0.5f₀ and option Alt (ii)-4 for SCS 2f₀ and 4f₀.

FIG. 16 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-2 for SCS 2f₀ and 4f₀.

FIG. 17 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-3 for SCS 2f₀ and 4f₀.

FIG. 18 is a diagram of a graph illustrating an example of reference PRBfor mixed numerologies.

FIG. 19 is a diagram of a graph of an example of mixed numerologies inFDM manner.

FIG. 20 is a flowchart of an embodiment of a method 2100 for determininga frequency location indexing in wideband CC

FIG. 21 is a block diagram of component modules.

Corresponding numerals and symbols in the different figures generallyrefer to corresponding parts unless otherwise indicated. The figures aredrawn to clearly illustrate the relevant aspects of the embodiments andare not necessarily drawn to scale.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

It should be understood at the outset that although an illustrativeimplementation of one or more embodiments are provided below, thedisclosed systems and/or methods may be implemented using any number oftechniques, whether currently known or not. The disclosure should in noway be limited to the illustrative implementations, drawings, andtechniques illustrated below, including the exemplary designs andimplementations illustrated and described herein, but may be modifiedwithin the scope of the appended claims along with their full scope ofequivalents.

5G New Radio (NR) wideband CC will support several features. Abasestation (e.g., a gNB) can operate simultaneously as wideband CC forsome UEs and as a set of intra-band contiguous CCs with CA for otherUEs. It is beneficial to allow zero guardband between CCs withinwideband CC and the lack of a guardband for certain scenarios should betaken it into account when performing channel raster. If there arescenarios where guard band is considered necessary, it may be beneficialto minimize the number of subcarriers for guardband between CCs withinwideband CC. Additionally, 5G NR will likely support single and multiplesynchronization signal (SS) block transmissions in wideband CC in thefrequency domain. For non CA UE with a smaller BW capability andpotentially for CA UE, the measurement gap for RRM measurement andpotentially other purposes (e.g., path loss measurement for UL powercontrol) using SS block will be supported (if it is agreed that there isno SS block in the active BW part(s)). The UE may be informed of thepresence and parameters of the SS block(s) and parameters used for RRMmeasurement via either, for example, RMSI signaling, other systeminformation, or RRC signaling.

In terms of how UEs access the wideband carrier, UEs can be categorizedinto two types: Type A and Type B. Type A UEs operate in intra-bandcarrier aggregation (CA) mode (contiguous or non-contiguous). Type B UEsoperate in single wideband mode. Both types of UEs need to use DLreference signals (RS) such as DMRS and CSI-RS for different purposes.Since each DL RS sequence is a function of a frequency location index(together with some other parameters), it is more efficient that alltypes of UEs use the same frequency location indexing for the purpose ofDL RS sequence generation. In NR, it is possible that the UE may notknow the bandwidth of its component carrier (CC). Therefore, thefrequency location indexing should be agnostic to the CC bandwidth.

Disclosed herein are systems and methods for using a reference point forfrequency location indexing. More specifically, embodiments of thepresent disclosure may use a single frequency reference point forfrequency location indexing for reference signal generation by all typesUEs in a wideband component carrier. In various embodiments, thereference point may be one of the following: 1) a predefined referencepoint with respect to the location of reference SS block; 2) thelocation of a (downlink) DC subcarrier of wideband CC; or 3) thelocation of the reference point is signaled through remaining minimumsystem information (RMSI) or other system information. In an embodiment,there are two types of carriers: 1) Wideband Component Carrier (WCC) and2) Normal Component Carrier (NCC).

In accordance with an embodiment of the present disclosure, a method forresource block (RB) indexing in a user equipment (UE) includesobtaining, at the UE, a UE-independent frequency reference point. Themethod also includes determining, by the UE, a UE-independent index ofan RB according to the UE-independent frequency reference point.

In accordance with an embodiment of the present disclosure, a method forresource block (RB) indexing in a base station includes transmitting, toa user equipment (UE), a UE-independent frequency reference point. TheUE-independent frequency reference point is for determining aUE-independent index of an RB.

In accordance with an embodiment of the present disclosure, a userequipment (UE) includes a non-transitory memory storage comprisinginstructions and one or more processors in communication with thenon-transitory memory storage. The one or more processors executeinstructions for obtaining a UE-independent frequency reference point.The one or more processors also execute instructions for determining aUE-independent index of an RB according to the UE-independent frequencyreference point.

In accordance with an embodiment of the present disclosure, a basestation includes a non-transitory memory storage comprising instructionsand one or more processors in communication with the non-transitorymemory storage. The one or more processors execute instructions fortransmitting, to a user equipment (UE), a UE-independent frequencyreference point. The UE-independent frequency reference point is fordetermining a UE-independent index of an RB.

In accordance with an embodiment of the present disclosure, a method forfrequency location indexing in a user equipment (UE) for widebandcomponent carrier (CC) includes receiving, at the UE, a UE independentfrequency reference point. The method also includes determining, by theUE, the UE independent frequency location index of a frequency locationaccording to the UE independent frequency reference point.

In accordance with an embodiment of the present disclosure, a wirelessdevice for frequency location indexing for wideband component carrier(CC) includes a non-transitory memory storage comprising instructionsand one or more processors in communication with the non-transitorymemory storage. The one or more processors execute the instructions forreceiving, at the UE, a UE independent frequency reference point. Theone or more processors also execute the instructions for determining, bythe UE, the UE independent frequency location index of a frequencylocation according to the UE independent frequency reference point.

In accordance with an embodiment of the present disclosure, anon-transitory computer-readable medium storing computer instructionsfor frequency location indexing for wideband component carrier (CC),that when executed by one or more processors, cause the one or moreprocessors to receive, at the UE, a UE independent frequency referencepoint. The instructions, when executed by the one or more processorsalso cause the one or more processors to determine, by the UE, the UEindependent frequency location index of a frequency location accordingto the UE independent frequency reference point.

Optionally, in any of the preceding aspects, the reference point is alowest subcarrier of a lowest RB for a given numerology.

Optionally, in any of the preceding aspects, obtaining theUE-independent frequency reference point includes receiving an offsetsignaled in a remaining system information (RMSI). The offset isexpressed in terms of a number of RBs. Obtaining the UE-independentfrequency reference point also includes determining the UE-independentfrequency reference point from the offset.

Optionally, in any of the preceding aspects, the method also includesreceiving an SS block. The SS block is one of a plurality of SS blocks.The offset is from a lowest subcarrier of the SS block to theUE-independent frequency reference point.

Optionally, in any of the preceding aspects, the SS block of theplurality of SS blocks corresponds to the RMSI used for signaling theoffset.

Optionally, in any of the preceding aspects, the offset is from a centerfrequency of a carrier to the UE-independent frequency reference point.

Optionally, in any of the preceding aspects, the UE-independentfrequency reference point is a first frequency reference point and theUE-independent index is a first index. Before obtaining the firstfrequency reference point, the method further includes obtaining asecond frequency reference point. The method also further includesdetermining a second index of another RB according to the secondfrequency reference point, the another RB for decoding the RMSI or aCORESET of the RMSI.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the frequency location comprises a physicalresource block (PRB).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedreference point with respect to a location of a referencesynchronization signal (SS) block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a startingsubcarrier or starting physical resource block (PRB) of the reference SSblock.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a last subcarrieror last physical resource block (PRB) of the reference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a middlesubcarrier, a middle physical resource block (PRB), or center frequencyof the reference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or predefined physical resource block (PRB) within thereference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or predefined physical resource block (PRB) within a commonresource region for receiving remaining minimum system information(RMSI) of the SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or physical resource block (PRB) outside of the reference SSblock, the predefined subcarrier or predefined physical resource block(PRB) having a predefined offset with respect to a specified part of thereference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the frequency location index of a physicalresource block (PRB) is determined according to a distance of the PRB toa reference point.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the distance is provided in a number of PRBs.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference SS block comprises a single SSblock within a wideband component carrier (WCC).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the method further includes receiving an SSblock, wherein the SS block is one of a plurality of SS blocks, whereina frequency distance between consecutive one of the plurality of SSblocks is fixed and predefined, and wherein the reference point isdetermined according to the SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the distance between consecutive ones of theplurality of SS blocks is uniform.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the distance between a first pair ofconsecutive ones of the plurality of SS blocks is different from thedistance between a second pair of consecutive ones of the plurality ofSS blocks.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that a relative frequency distance of SS blocks issignaled in system information.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the system information comprises remainingminimum system information (RMSI).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the frequency location indexing for sequencesgenerated used for RMSI and its control resource set (CORESET) isdifferent from the frequency location indexing for sequences used forunicast data and so a specific reference signal (RS) is used for theRMSI and its CORESET.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that a frequency index of each of the plurality ofSS blocks is signaled in a corresponding system information.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the system information comprises one of aphysical broadcast channel (PBCH) or an RMSI.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a location of adownlink direct current (DC) subcarrier of a wideband component carrier(WCC).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that a part of the DC information is signaled in aphysical broadcast channel (PBCH).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point is determined according toa predefined location of the DC in a common bandwidth part (BWP) if theDC is present in the common BWP.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that a location of the DC is provided as an offsetwith respect to a reference point of the SS block or a reference pointof a common bandwidth part (BWP).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point is signaled through systeminformation.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the system information comprises remainingminimum system information (RMSI).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or a predefined physical resource block (PRB) within thereference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or a predefined physical resource block (PRB) within a commonresource region for receiving remaining minimum system information(RMSI) of the SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference point comprises a predefinedsubcarrier or predefined physical resource block (PRB) outside of thereference SS block, the predefined subcarrier or PRB having a predefinedoffset with respect to a specified part of the reference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the method further includes obtaining a defaultnumerology of a reference physical resource block (PRB) and determininga numerology of a first PRB according to the default numerology.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the frequency reference point of a firstnumerology is determined according to the frequency reference point of adefault numerology using a predefined rule.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the predefined rule for a numerology withsubcarrier spacing (SCS) smaller than the default SCS defines thereference physical resource block (PRB) as a specified PRBs among thePRBs that are included in the reference PRB of the default numerology.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the specified PRB is predefined or signaledthrough system information.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference PRB of SCS 2^(−n)f₀, with n≥1comprises a k_(n)'th PRB among the PRBs included in the reference PRB ofthe default SCS f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that k_(n) is one of 1, 2^(n), 2^(n-1), 2^(n-1)+1,and min(k, 2^(n)).

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference PRB of SCS 2^(−n)f₀, with n≥1comprises a last PRB if n is odd and a first PRB if n is even among thePRBs included in the reference PRB of SCS 2^(−n+1)f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the reference PRB of SCS 2^(−n)f₀, with n≥1comprises a first PRB if n is odd and a last PRB if n is even among thePRBs included in the reference PRB of SCS 2^(−n+1)f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the predefined rule for a numerology withsubcarrier spacing (SCS) larger than the default SCS is used to derive aPRB grid and a reference PRB of a larger SCS from the reference PRB ofthe default SCS.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that, for any SCS 2^(n)f₀, with n≥1, the referencePRB of SCS 2^(n)f₀ is left-aligned with the reference PRB of the defaultSCS f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that, for any SCS 2^(n)f₀, with n≥1, the referencePRB of SCS 2^(n)f₀ is right-aligned with the reference PRB of thedefault SCS f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that, for any SCS 2^(n)f₀, with n≥1, if n is odd,the reference PRB of SCS 2^(n-1)f₀ is right-aligned with the referencePRB of SCS 2^(n)f₀ and if n is even, the reference PRB of SCS 2^(n-1)f₀is left-aligned with the reference PRB of SCS 2^(n)f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that, for any SCS 2^(n)f₀, with n≥1, if n is odd,the reference PRB of SCS 2^(n-1)f₀ is left-aligned with the referencePRB of SCS 2^(n)f₀ and if n is even, the reference PRB of SCS 2^(n-1)f₀is right-aligned with the reference PRB of SCS 2^(n)f₀.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that only one SS block in a frequency domain has acorresponding RMSI and that the only one SS block is the reference SSblock.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that one bit in a PBCH of an SS block indicateswhether the SS block is a reference SS block.

Optionally, in any of the preceding aspects, another implementation ofthe aspect provides that the frequency location indexing for sequencesgenerated used for RMSI and its CORESET is the same as the frequencylocation indexing for sequences used for unicast data.

FIG. 1 illustrates an example communication system 100 in whichembodiments of the present disclosure could be implemented. In general,the communication system 100 enables multiple wireless or wired elementsto communicate data and other content. The purpose of the communicationsystem 100 may be to provide content (voice, data, video, text) viabroadcast, narrowcast, user device to user device, etc. Thecommunication system 100 may operate by sharing resources such asbandwidth.

In this example, the communication system 100 includes electronicdevices (ED) 110 a-110 c, radio access networks (RANs) 120 a-120 b, acore network 130, a public switched telephone network (PSTN) 140, theinternet 150, and other networks 160. Although certain numbers of thesecomponents or elements are shown in FIG. 1, any reasonable number ofthese components or elements may be included in the communication system100.

The EDs 110 a-110 c are configured to operate, communicate, or both, inthe communication system 100. For example, the EDs 110 a-110 c areconfigured to transmit, receive, or both via wireless or wiredcommunication channels. Each ED 110 a-110 c represents any suitable enduser device for wireless operation and may include such devices (or maybe referred to) as a user equipment/device (UE), wirelesstransmit/receive unit (WTRU), mobile station, fixed or mobile subscriberunit, cellular telephone, station (STA), machine type communication(MTC) device, personal digital assistant (PDA), smartphone, laptop,computer, tablet, wireless sensor, or consumer electronics device.

In FIG. 1, the RANs 120 a-120 b include base stations 170 a-170 b,respectively. Each base station 170 a-170 b is configured to wirelesslyinterface with one or more of the EDs 110 a-110 c to enable access toany other base station 170 a-170 b, the core network 130, the PSTN 140,the internet 150, and/or the other networks 160. For example, the basestations 170 a-170 b may include (or be) one or more of severalwell-known devices, such as a base transceiver station (BTS), a Node-B(NodeB), an evolved NodeB (eNodeB), a Home eNodeB, a gNodeB, atransmission point (TP), a site controller, an access point (AP), or awireless router. Any ED 110 a-110 c may be alternatively or additionallyconfigured to interface, access, or communicate with any other basestation 170 a-170 b, the internet 150, the core network 130, the PSTN140, the other networks 160, or any combination of the preceding. Thecommunication system 100 may include RANs, such as RAN 120 b, whereinthe corresponding base station 170 b accesses the core network 130 viathe internet 150, as shown.

The EDs 110 a-110 c and base stations 170 a-170 b are examples ofcommunication equipment that can be configured to implement some or allof the functionality and/or embodiments described herein. In theembodiment shown in FIG. 1, the base station 170 a forms part of the RAN120 a, which may include other base stations, base station controller(s)(BSC), radio network controller(s) (RNC), relay nodes, elements, and/ordevices. Any base station 170 a, 170 b may be a single element, asshown, or multiple elements, distributed in the corresponding RAN, orotherwise. Also, the base station 170 b forms part of the RAN 120 b,which may include other base stations, elements, and/or devices. Eachbase station 170 a-170 b transmits and/or receives wireless signalswithin a particular geographic region or area, sometimes referred to asa “cell” or “coverage area”. A cell may be further divided into cellsectors, and a base station 170 a-170 b may, for example, employmultiple transceivers to provide service to multiple sectors. In someembodiments there may be established pico or femto cells where the radioaccess technology supports such. In some embodiments, multipletransceivers could be used for each cell, for example usingmultiple-input multiple-output (MIMO) technology. The number of RAN 120a-120 b shown is exemplary only. Any number of RAN may be contemplatedwhen devising the communication system 100.

The base stations 170 a-170 b communicate with one or more of the EDs110 a-110 c over one or more air interfaces 190 using wirelesscommunication links e.g. radio frequency (RF), microwave, infrared (IR),etc. The air interfaces 190 may utilize any suitable radio accesstechnology. For example, the communication system 100 may implement oneor more channel access methods, such as code division multiple access(CDMA), time division multiple access (TDMA), frequency divisionmultiple access (FDMA), orthogonal FDMA (OFDMA), or single-carrier FDMA(SC-FDMA) in the air interfaces 190.

A base station 170 a-170 b may implement Universal MobileTelecommunication System (UMTS) Terrestrial Radio Access (UTRA) toestablish an air interface 190 using wideband CDMA (WCDMA). In doing so,the base station 170 a-170 b may implement protocols such as HSPA, HSPA+optionally including HSDPA, HSUPA or both. Alternatively, a base station170 a-170 b may establish an air interface 190 with Evolved UTMSTerrestrial Radio Access (E-UTRA) using LTE, LTE-A, and/or LTE-B. It iscontemplated that the communication system 100 may use multiple channelaccess functionality, including such schemes as described above. Otherradio technologies for implementing air interfaces include IEEE 802.11,802.15, 802.16, CDMA2000, CDMA2000 1×, CDMA2000 EV-DO, IS-2000, IS-95,IS-856, GSM, EDGE, and GERAN. Of course, other multiple access schemesand wireless protocols may be utilized.

The RANs 120 a-120 b are in communication with the core network 130 toprovide the EDs 110 a-110 c with various services such as voice, data,and other services. The RANs 120 a-120 b and/or the core network 130 maybe in direct or indirect communication with one or more other RANs (notshown), which may or may not be directly served by core network 130, andmay or may not employ the same radio access technology as RAN 120 a, RAN120 b or both. The core network 130 may also serve as a gateway accessbetween (i) the RANs 120 a-120 b or EDs 110 a-110 c or both, and (ii)other networks (such as the PSTN 140, the internet 150, and the othernetworks 160). In addition, some or all of the EDs 110 a-110 c mayinclude functionality for communicating with different wireless networksover different wireless links using different wireless technologiesand/or protocols. Instead of wireless communication (or in additionthereto), the EDs may communicate via wired communication channels to aservice provider or switch (not shown), and to the internet 150. PSTN140 may include circuit switched telephone networks for providing plainold telephone service (POTS). Internet 150 may include a network ofcomputers and subnets (intranets) or both, and incorporate protocols,such as IP, TCP, UDP. EDs 1100 a-110 c may be multimode devices capableof operation according to multiple radio access technologies, andincorporate multiple transceivers necessary to support such.

FIGS. 2A and 2B illustrate example devices that may implement themethods and teachings according to this disclosure. In particular, FIG.2A illustrates an example ED 110, and FIG. 2B illustrates an examplebase station 170. These components could be used in the communicationsystem 100 or in any other suitable system.

As shown in FIG. 2A, the ED 110 includes at least one processing unit200. The processing unit 200 implements various processing operations ofthe ED 110. For example, the processing unit 200 could perform signalcoding, data processing, power control, input/output processing, or anyother functionality enabling the ED 110 to operate in the communicationsystem 100. The processing unit 200 may also be configured to implementsome or all of the functionality and/or embodiments described in moredetail above. Each processing unit 200 includes any suitable processingor computing device configured to perform one or more operations. Eachprocessing unit 200 could, for example, include a microprocessor,microcontroller, digital signal processor, field programmable gatearray, or application specific integrated circuit.

The ED 110 also includes at least one transceiver 202. The transceiver202 is configured to modulate data or other content for transmission byat least one antenna or Network Interface Controller (NIC) 204. Thetransceiver 202 is also configured to demodulate data or other contentreceived by the at least one antenna 204. Each transceiver 202 includesany suitable structure for generating signals for wireless or wiredtransmission and/or processing signals received wirelessly or by wire.Each antenna 204 includes any suitable structure for transmitting and/orreceiving wireless or wired signals. One or multiple transceivers 202could be used in the ED 110. One or multiple antennas 204 could be usedin the ED 110. Although shown as a single functional unit, a transceiver202 could also be implemented using at least one transmitter and atleast one separate receiver.

The ED 110 further includes one or more input/output devices 206 orinterfaces (such as a wired interface to the internet 150). Theinput/output devices 206 permit interaction with a user or other devicesin the network. Each input/output device 206 includes any suitablestructure for providing information to or receiving information from auser, such as a speaker, microphone, keypad, keyboard, display, or touchscreen, including network interface communications.

In addition, the ED 110 includes at least one memory 208. The memory 208stores instructions and data used, generated, or collected by the ED110. For example, the memory 208 could store software instructions ormodules configured to implement some or all of the functionality and/orembodiments described above and that are executed by the processingunit(s) 200. Each memory 208 includes any suitable volatile and/ornon-volatile storage and retrieval device(s). Any suitable type ofmemory may be used, such as random access memory (RAM), read only memory(ROM), hard disk, optical disc, subscriber identity module (SIM) card,memory stick, secure digital (SD) memory card, and the like.

As shown in FIG. 2B, the base station 170 includes at least oneprocessing unit 250, at least one transmitter 252, at least one receiver254, one or more antennas 256, at least one memory 258, and one or moreinput/output devices or interfaces 266. A transceiver, not shown, may beused instead of the transmitter 252 and receiver 254. A scheduler 253may be coupled to the processing unit 250. The scheduler 253 may beincluded within or operated separately from the base station 170. Theprocessing unit 250 implements various processing operations of the basestation 170, such as signal coding, data processing, power control,input/output processing, or any other functionality. The processing unit250 can also be configured to implement some or all of the functionalityand/or embodiments described in more detail above. Each processing unit250 includes any suitable processing or computing device configured toperform one or more operations. Each processing unit 250 could, forexample, include a microprocessor, microcontroller, digital signalprocessor, field programmable gate array, or application specificintegrated circuit.

Each transmitter 252 includes any suitable structure for generatingsignals for wireless or wired transmission to one or more EDs or otherdevices. Each receiver 254 includes any suitable structure forprocessing signals received wirelessly or by wire from one or more EDsor other devices. Although shown as separate components, at least onetransmitter 252 and at least one receiver 254 could be combined into atransceiver. Each antenna 256 includes any suitable structure fortransmitting and/or receiving wireless or wired signals. Although acommon antenna 256 is shown here as being coupled to both thetransmitter 252 and the receiver 254, one or more antennas 256 could becoupled to the transmitter(s) 252, and one or more separate antennas 256could be coupled to the receiver(s) 254. Each memory 258 includes anysuitable volatile and/or non-volatile storage and retrieval device(s)such as those described above in connection to the ED 110. The memory258 stores instructions and data used, generated, or collected by thebase station 170. For example, the memory 258 could store softwareinstructions or modules configured to implement some or all of thefunctionality and/or embodiments described above and that are executedby the processing unit(s) 250.

Each input/output device 266 permits interaction with a user or otherdevices in the network. Each input/output device 266 includes anysuitable structure for providing information to or receiving/providinginformation from a user, including network interface communications.

Frame structures have been proposed that are flexible in terms of theuse of differing numerologies. A numerology is defined as the set ofphysical layer parameters of the air interface that are used tocommunicate a particular signal. A numerology is described in terms ofat least subcarrier spacing and OFDM symbol duration, and may also bedefined by other parameters such as fast Fourier transform (FFT)/inverseFFT (IFFT) length, transmission time slot length, and cyclic prefix (CP)length or duration. In some implementations, the definition of thenumerology may also include which one of several candidate waveforms isused to communicate the signal. Possible waveform candidates mayinclude, but are not limited to, one or more orthogonal ornon-orthogonal waveforms selected from the following: OrthogonalFrequency Division Multiplexing (OFDM), Filtered OFDM (f-OFDM), FilterBank Multicarrier (FBMC), Universal Filtered Multicarrier (UFMC),Generalized Frequency Division Multiplexing (GFDM), Single CarrierFrequency Division Multiple Access (SC-FDMA), Low Density SignatureMulticarrier Code Division Multiple Access (LDS-MC-CDMA), Wavelet PacketModulation (WPM), Faster Than Nyquist (FTN) Waveform, low Peak toAverage Power Ratio Waveform (low PAPR WF), Pattern Division MultipleAccess (PDMA), Lattice Partition Multiple Access (LPMA), Resource SpreadMultiple Access (RSMA), and Sparse Code Multiple Access (SCMA).

These numerologies may be scalable in the sense that subcarrier spacingsof different numerologies are multiples of each other, and time slotlengths of different numerologies are also multiples of each other. Sucha scalable design across multiple numerologies provides implementationbenefits, for example scalable total OFDM symbol duration in a timedivision duplex (TDD) context.

Table 1 below shows the parameters associated with some examplenumerologies, in the four columns under “Frame structure”. Frames can beconfigured using one or a combination of the four scalable numerologies.For comparison purposes, in the right hand column of the table, theconventional fixed LTE numerology is shown. The first column is for anumerology with 60 kHz subcarrier spacing, which also has the shortestOFDM symbol duration because OFDM symbol duration varies inversely withsubcarrier spacing. This may be suitable for ultra-low latencycommunications, such as Vehicle-to-Any (V2X) communications. The secondcolumn is for a numerology with 300 kHz subcarrier spacing. The thirdcolumn is for a numerology with 15 kHz subcarrier spacing. Thisnumerology has the same configuration as in LTE, except there are only 7symbols in a time slot. This may be suitable for broadband services. Thefourth column is for a numerology with 7.5 kHz spacing, which also hasthe longest OFDM symbol duration among the four numerologies. This maybe useful for coverage enhancement and broadcasting. Additional uses forthese numerologies will be or become apparent to persons of ordinaryskill in the art. Of the four numerologies listed, those with 300 kHzand 60 kHz subcarrier spacings are more robust to Doppler spreading(fast moving conditions), because of the wider subcarrier spacing. It isfurther contemplated that different numerologies may use differentvalues for other physical layer parameters, such as the same subcarrierspacing and different cyclic prefix lengths.

It is further contemplated that other subcarrier spacings may be used,such as higher or lower subcarrier spacings. As illustrated in theexample above, the subcarrier spacing of each numerology (7.5 kHz, 15kHz, 300 kHz, 60 kHz) can be a factor of 2^(n) times the smallestsubcarrier spacing, where n is an integer. Larger subcarrier spacingsthat are also related by a factor of 2^(n), such as 120 kHz, may also oralternatively be used. Smaller subcarrier spacings that are also relatedby a factor of 2^(n), such as 3.75 kHz, may also or alternatively beused. The symbol durations of the numerologies may also be related by afactor of 2^(n). Two or more numerologies that are related in this wayare sometimes referred to as scalable numerologies.

In other examples, a more limited scalability may be implemented, inwhich two or more numerologies all have subcarrier spacings that areinteger multiples of the smallest subcarrier spacing, withoutnecessarily being related by a factor of 2^(n). Examples include 15 kHz,300 kHz, 45 kHz, 600 kHz, 120 kHz subcarrier spacings.

In still other examples, non-scalable subcarrier spacings may be used,which are not all integer multiples of the smallest subcarrier spacing,such as 15 kHz, 20 kHz, 30 kHz, 60 kHz.

In Table 1, each numerology uses a first cyclic prefix length for afirst number of OFDM symbols, and a second cyclic prefix length for asecond number of OFDM symbols. For example, in the first column under“Frame structure”, the time slot includes 3 symbols with a cyclic prefixlength of 1.04 μs followed by 4 symbols with a cyclic prefix length of1.3 μs.

TABLE 1 Example set of Numerologies Baseline Parameters Frame structure(LTE) time slot 0.125 ms 0.25 ms 0.5 ms 1 ms TTI = 1 ms LengthSubcarrier 60 kHz 30 kHz 15 kHz 7.5 kHz 15 kHz spacing FFT size 512 10242048 4096 2048 Symbol 16.67 μs 33.33 μs 66.67 μs 133.33 μs 66.67 μsduration #symbols in 7 (3, 4) 7 (3, 4) 7 (3, 4) 7 (3, 4) 14 (2, 12) eachtime slot CP length 1.04 μs, 2.08 μs, 4.17 μs, 8.33 μs, 5.2 μs, 1.30 μs2.60 μs 5.21 μs 10.42 μs 4.7 μs (32, 40 (64, 80 (128, 160 (256, 320(160, 144 point) point) point) point) point) CP 6.67% 6.67% 6.67% 6.67%6.67% overhead BW (MHz) 20 20 20 20 20

In Table 2, an example set of numerologies is shown, in which differentcyclic prefix lengths can be used in different numerologies having thesame subcarrier spacing.

TABLE 2 Example numerology with different CP lengths Subcarrier spacing(kHz) 15 30 30 60 60 60 Useful duration T_(u) (μs) 66.67 33.33 33.3316.67 16.67 16.67 CP length (μs) (1) 5.2 5.73 2.6 2.86 1.3 3.65 CPlength (μs) (6 or 12) 4.7 5.08 2.34 2.54 1.17 3.13 # of symbols per TTI7 (1, 6) 13 (1, 12) 7 (1, 6) 13 (1, 12) 7 (1, 6) 25 (10, 15) TTI (ms)0.5 0.5 0.25 0.25 0.125 0.5 CP overhead 6.70% 13.30% 6.70% 13.30% 6.70%16.67%

It should be understood that the specific numerologies of the examplesof Tables 1 and 2 are for illustration purposes, and that a flexibleframe structure combining other numerologies can alternatively beemployed.

OFDM-based signals can be employed to transmit a signal in whichmultiple numerologies coexist simultaneously. More specifically,multiple sub-band OFDM signals can be generated in parallel, each withina different sub-band, and each sub-band having a different subcarrierspacing (and more generally with a different numerology). The multiplesub-band signals are combined into a single signal for transmission, forexample for downlink transmissions. Alternatively, the multiple sub-bandsignals may be transmitted from separate transmitters, for example foruplink transmissions from multiple electronic devices (EDs), which maybe user equipment (UEs). In a specific example, filtered OFDM (f-OFDM)can be employed by using filtering to shape the frequency spectrum ofeach sub-band OFDM signal, thereby producing a frequency localizedwaveform, and then combining the sub-band OFDM signals for transmission.f-OFDM lowers out-of-band emission and improves transmission, andaddresses the non-orthogonality introduced as a result of the use ofdifferent subcarrier spacings. Alternatively, a different approach canbe used to achieve a frequency localized waveform, such as windowed OFDM(W-OFDM).

The use of different numerologies can allow the coexistence of a diverseset of use cases having a wide range quality of service (QoS)requirements, such as different levels of latency or reliabilitytolerance, as well as different bandwidth or signaling overheadrequirements. In one example, the base station can signal to the ED anindex representing a selected numerology, or a single parameter (e.g.,subcarrier spacing) of the selected numerology. The signaling can bedone in a dynamic or a semi-static manner, for example in a controlchannel such as the physical downlink control channel (PDCCH) or indownlink control information (DCI). Based on this signaling, the ED maydetermine the parameters of the selected numerology from otherinformation, such as a look-up table of candidate numerologies stored inmemory.

FIG. 3 is a diagram of an embodiment of a WCC 302. WCC 302 includes aplurality of normal component carriers (NCCs) 304. Each NCC 304 includesa plurality of subcarriers each with a specified bandwidth. The WCC 302also includes a plurality of SS blocks 308. The WCC 302 also includes areference point 306. The reference point 306 is used for frequencylocation indexing. In an embodiment, the reference point 306 is apredefined reference point with respect to the location of a referenceSS block. For example, the reference point 306 is a distance Δ₀ from thebeginning of a reference SS block 308, a distance Δ₁ from the beginningof a second reference SS block 308, and a distance Δ₂ from a thirdreference SS block 308. The distance may be measured in the number ofsubcarriers between the reference point 306 and the particular referenceSS block 308 or may be measured in the number of physical resourceblocks (PRBs) between the reference point 306 and the particularreference SS block 308 or may be measured in difference in frequency.Other methods of distance measurement may also be used.

In an embodiment, the same frequency location indexing for RS sequencegeneration is used for both RMSI and unicast data. The reference pointfor the RS sequence generation is obtained by the UE before decoding theRMSI. The reference point is used to generate the RS sequences for bothRMSI and all unicast data such as NR-PDSCH. In one embodiment, the sametype of sequence generation is used for RMSI and its CORESET and forunicast data. In one embodiment, the downlink DC subcarrier of widebandCC is taken as the reference point. In another embodiment, an SS blockis taken as the reference SS block with respect to which the referencepoint is obtained.

In embodiment in which the downlink DC subcarrier of wideband CC istaken as the reference point, the DC location is signaled in PBCH ofeach SS block. The location of DC is represented as an offset withrespect to a predefined point in the SS block or a predefined point inthe common BWP.

In embodiment in which an SS block is taken as the reference SS block,in one embodiment, only one SS block in frequency has a correspondingRMSI. This SS block is the reference SS block and a predefined pointwith respect to this SS block is taken as the reference point. In thecase of multiple SS blocks in frequency in wideband CC, only one of themhas a corresponding RMSI. All UEs in wideband CC need to detect this SSblock to be able to obtain the reference point. The indication of thisSS block can be done through PBCH by indicating whether or not there isa corresponding RMSI to the SS block. The SS block that has acorresponding RMSI according to the indication in its PBCH is taken asthe reference SS block by the UE. In a second embodiment, one bit inPBCH indicates whether the SS block can be considered as the referenceSS block. If an SS block is indicated as the reference SS block, apredefined point with respect to this SS block is taken as the referencepoint.

In another embodiment, different frequency location indexings forsequence generation are used for RMSI (and its CORESET) and unicastdata. UE needs to first decode RMSI to be able to obtain the referencepoint. A specific RS is used for control resource set (CORESET) of RMSIand NR-PDSCH for RMSI. After obtaining the reference point, the UE usesit to generate the RS sequences for all unicast data such as NR-PDSCH.In one embodiment, the reference point 306 is identified as a locationof a downlink (DL) DC subcarrier of wideband CC. In a second embodiment,an SS block is taken the reference SS block with respect to which thereference point is obtained. In a third embodiment, the reference point306 is signaled to a UE through system information such as, for example,remaining minimum system information (RMSI).

FIG. 4 is a diagram of an embodiment of a system 400 of physicalresource blocks (PRBs) in the frequency domain. The system 400 includesa reference SS block 402. The reference SS block 402 includes aplurality of PRBs. In the depicted example, the SS block 402 includesPRB#−1, a reference PRB 404, PRB#1, and PRB#2. In an embodiment, thereference point is a predefined reference point with respect to thefrequency location of a reference SS block 402. In the case in whichonly a single SS block is transmitted within a WCC, the reference pointcan be defined as one of the PRBs (i.e., the reference PRB 404) withinthe reference SS block 402. All other PRBs may be indexed based on theirdistance from the reference PRB 404 as either −1, −2, etc. for PRBs withlower frequencies than the reference PRB 404 or 1, 2, etc. for PRBs withhigher frequencies than the reference PRB. The numbers 1, −1, 2, −2,etc., indicate whether the PRB is the 1^(st) PRB (i.e., PRB#1) after thereference PRB 404, the 1^(st) PRB (i.e., PRB#−1) before the referencePRB 404, the 2^(nd) PRB (i.e., PRB#2) after the reference PRB 404, the2^(nd) PRB (i.e., PRB#−2) before the reference PRB 404, etc.

If an SS block is taken as the reference SS block, then the followingoptions may be used to identify a reference point as a specific pointrelative to the reference SS block. The reference point may be, forexample, one of the following: 1) the starting subcarrier or PRB of thereference SS block, 2) the last subcarrier or PRB of the reference SSblock, 3) the middle subcarrier or middle PRGB or the center frequencyof the reference SS block, 4) a specific predefined subcarrier or PRBwithin the reference SS block, 5) a specific predefined subcarrier orPRB within the common resource region for receiving RMSI (sometimesreferred to as the common bandwidth part or common BWP) of the referenceSS block, or 6) a specific predefined subcarrier or PRB outside of thereference SS block with a known offset with respect to the beginning,end, middle, or any other reference point of the reference SS block.

FIGS. 5-10 are block diagrams each illustrating an option 500, 600, 700,800, 900, 1000 for identifying the reference point as a specific pointrelative to the reference SS block. In option I 500 in FIG. 5, thereference point 506 is a first PRB of the reference SS block 504 in thecommon BWP 502. In option II 600 in FIG. 6, the reference point 606 isthe last PRB of the reference SS block 604 within the common BWP 602. Inoption III 700 in FIG. 7, the reference point 706 is one of the middleSS PRBs of the reference SS block 704 within common BWP 702. In optionIV 800 in FIG. 8, the reference point 806 is a specific PRB within thereference SS block 804 in common BWP 802. In option V 900 in FIG. 9, thereference point 906 is a specific PRB outside of the reference SS block904 but within the common BWP 902. In option VI 1000 in FIG. 10, thereference point 1006 is a specific PRB outside both the reference SSblock 1004 and the common BWP 1002.

In an embodiment, the frequency index of any PRB is determined by itsdistance (in number of PRBs) to the reference point.

In embodiments in which the WCC includes a single SS block, thereference SS block is the single SS block within the WCC.

If the WCC includes multiple SS blocks, the relative distance between SSblocks may be fixed or signaled. If the relative frequency distance ofSS blocks is fixed and predefined, the distance may be fixed and uniformor fixed and non-uniform.

FIG. 11 is a diagram of an embodiment of a system 1100 of subcarriers inthe frequency domain showing fixed uniform distance between consecutiveSS blocks 1104, 1106, 1108 in a WCC. System 1100 includes a WCC 1102having three SS blocks 1104, 1106, 1108. The distance, Δf betweenconsecutive pairs of SS blocks 1104, 1106, 1108 is the same for allconsecutive pairs of SS blocks 1104, 1106, 1108 (e.g., between SS block1104 and SS block 1106 or between SS block 1106 and SS block 1108).

FIG. 12 is a diagram of an embodiment of a system 1200 of subcarriers inthe frequency domain showing fixed uniform distance between consecutiveSS blocks 1204, 1206, 1208 in a WCC. The distance, Δf₁ between a firstconsecutive pair of SS blocks 1204, 1206 (i.e., between SS block 1204and SS block 1206) is different from the distance, Δf₂, between a secondconsecutive pair of SS blocks 1206, 1208 (i.e., between SS block 1206and SS block 1208).

If the relative frequency distance of SS blocks is signaled in systeminformation such as, for example, RMSI, the relative frequency distancecan again be either uniform or non-uniform between consecutive SS blocksas illustrated in FIGS. 11 and 12.

In an embodiment, the frequency index of each SS block (i.e., SS block#i in FIGS. 11 and 12) is signaled in its corresponding PBCH, RMSI, orother system information.

In an embodiment, all UEs (both types A and B) obtain the same frequencylocation indexing as follows. First, the detected SS block is taken asthe reference SS block. If more than one SS blocks are detected, any ofthem can be taken as the reference SS block. Assume that SS block #i istaken as the reference SS block. The frequency location index of a PRBcan be determined based on one of the following methods depending onwhether the distance between SS blocks is uniform or no uniform. If thedistance between SS blocks is uniform, then the frequency locationindex, n, of a PRB is determined according to n=(distance of the PRB tothe reference point of the SS block #i)+i×Δf. If the distance between SSblocks i non-uniform, then the frequency location index, n, of a PRB isdetermined according to n=(distance of the PRB to the reference point ofthe SS block #i)+Δf₁+ . . . +Δf_(i). Therefore, the value of thefrequency location index, n, is independent of the reference SS block.

In another embodiment, the reference point of the frequency locationindexing for a uniform distance between SS blocks can be defined asreference point=(the reference point of SS block #i)−i×Δf. The referencepoint of the frequency location indexing for a non-uniform distancebetween SS blocks can be defined as reference point=(the reference pointof SS block #i)−(Δf₁+ . . . +Δf_(i)). Then, in either case, thefrequency location index of a PRB, n, is the distance of the PRB to thereference point.

In another embodiment, one of the multiple SS blocks in WCC ispredefined as reference SS block, e.g. SS block #j. Each UE afterdetecting one of the SS blocks, e.g. SS block #i, and obtaining thevalue of i from its corresponding PBCH, RMSI, or other systeminformation, and after obtaining the relative frequency distance of SSblocks through system information, such as RMSI, is able to find thelocation of the reference SS block, i.e. SS block #j. Then, it candetermine the location of the reference point by using the predefinedoffset and the location of the reference SS block.

In another embodiment, in which the reference point is identified as alocation of a DL DC subcarrier of WCC, a number of different methods maybe used to identify the reference point to the UE.

In one embodiment, part of the DC information is signaled to the UE in,for example, PBCH. The DC may or may not be present in the common BWP.If the DC is present in the common BWP, reference point is identified asa predefined location of the DC for common BWP. If the DC is not presentin the common BWP, then system information signaling (e.g., RMSI)indicates the location of the DC. In this case in which the DC is notpresent in the common BWP, the location of the DC may be presented as anoffset with respect to the reference point of the SS block or as areference point of the common BWP. In an embodiment, the frequencylocation indexing for sequences generated used for RMSI and its CORESETis different from the frequency location indexing for sequences used forunicast data and so a specific RS is used for the RMSI and its CORESET.

In a second embodiment in which the reference point is identified as alocation of a DL DC subcarrier of WCC, the DC location is signaledthrough system information such as, for example, RMSI. As with the caseof signaling the reference point with respect to the location of areference SS block, a specific predefined subcarrier or PRB within theSS block, the common BWP of the reference SS block, or a specificpredefined subcarrier or PRB outside of the reference SS block with aknown offset with respect to the beginning, end, middle, or any otherreference point of the reference SS block may be signaled to the UE butis done through system information, such as RMSI, rather than beingpredefined. In an embodiment, the frequency location indexing forsequences generated used for RMSI or other system information theirCORESETs is different from the frequency location indexing for sequencesused for unicast data and so a specific RS is used for the RMSI or othersystem information and their CORESETs.

In the embodiments of the present disclosure, using a single frequencyreference point for frequency location indexing allows for all types UEs(e.g., Type A intra-band carrier aggregation (CA) mode, and Type Bsingle wideband mode) in a wideband component carrier to moreefficiently generate reference signals.

In a further beneficial aspect, the disclosed methods of determining areference point for a UE to use to determine a frequency location indexin WCC are also applicable to systems that utilize mixed numerologies.In these cases, the SS blocks use a default numerology. After detectingan SS block, the PRB grid of the default numerology is obtained by theUE. In an embodiment, using a nested structure, the PRB grid of allnumerologies with subcarrier spacing (SCS) smaller than a default SCS isderived from the PRB grid of the default numerology. The reference PRBof the default numerology is the PRB which includes the reference pointof the default numerology. Once the reference PRB of the defaultnumerology is known to a UE (using, for example, any of the examplemethods discussed above), the reference PRB of the default numerology isused to obtain the reference PRB of any other numerology.

According to embodiments of the present disclosure, frequency locationindexing for RS sequence generation may be subcarrier spacing (i.e.,numerology) specific. In specific embodiments described below, thereference point for frequency location indexing of each subcarrierspacing or numerology is obtained from the reference point of thedefault subcarrier spacing based on a predefined rule. Examples ofpredefined rules for providing different subcarrier spacing specificfrequency location indexing are described below with reference to FIGS.13 to 19.

For any numerology with SCS smaller than the default SCS, the referencePRB is a specified PRB among PRBs that are included in the reference PRBof the default numerology. The “specified PRB” can be predefined orsignaled through RMSI or other system information.

Some alternatives for the reference PRB of SCS 2^(−n)f₀, with n≥1 arediscussed below, where f₀ is the default SCS.

In alternative A), the k_(n)'th PRB among the PRBs included in thereference PRB of SCS f₀. Examples of k_(n) are k_(n)=1 (first PRB),k_(n)=2^(n) (last PRB), k_(n)=2^(n-1), k_(n)=2^(n-1)+1, k_(n)=min(k,2^(n)) with k defined in the specification for the system.

In alternative B), the last PRB (if n is odd) and the first PRB (if n iseven) among the PRBs included in the reference PRB of SCS 2^(−n)+1f₀.

In alternative C), the first PRB (if n is odd) and the last PRB (if n iseven) among the PRBs included in the reference PRB of SCS 2^(−n)+1f₀.

In an embodiment, there are two alternatives for determining the PRBgrid of a numerology with SCS greater than the default SCS.

In alternative i), the PRB grid of the numerology is already known tothe UE (either by predefined rule or through signaling). The referencePRB of the numerology with SCS greater the default SCS is the PRB thatincludes the reference PRB of the default numerology.

In alternative ii), the reference PRB of the default numerologydetermines both the PRB grid and the reference PRB of a numerology withSCS greater than the default SCS. In this case, a predefined rule isused to derive the PRB grid and the reference PRB of a larger SCS fromthe reference PRB of the default SCS. In an embodiment, there are fourdifferent options for alternative ii).

In option Alt (ii)-1, for any SCS 2^(n)f₀, with n≥1, the reference PRBof SCS 2^(n)f₀ is left-aligned with the reference PRB of SCS f₀. As usedherein, the “right” refers to higher frequencies and “left” refers tolower frequencies. Thus, when two reference PRBs are “left-aligned”, thelowest frequencies of each reference PRB are aligned. Similarly, whentwo reference PRBs are “right-aligned”, the highest frequencies of eachreference PRB are aligned.

FIG. 13 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-1 for SCS 2f₀ and 4f₀. Thereference PRBs 1302, 1304 for numerologies with larger SCS than the SCSof the default numerology and the reference PRB 1308 for numerologieswith smaller SCS than the SCS of the default numerology are left alignedwith the reference PRB 1306 for the default numerology. Thus, whenreference PRBs 1302, 1304, 1306, 1308 are left aligned, the lowestfrequency of each reference PRB 1302, 1304, 1306, 1308 are aligned.

In option Alt (ii)-2, for any SCS 2^(n)f₀, with n≥1, the reference PRBof SCS 2^(n)f₀ is right-aligned with the reference PRB of SCS f₀.

FIG. 14 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=2^(n) for SCS 0.5f₀ and option Alt (ii)-2 for SCS 2f₀ and 4f₀. Thereference PRBs 1402, 1404 for numerologies with larger SCS than the SCSof the default numerology and the reference PRB 1408 for numerologieswith smaller SCS than the SCS of the default numerology are rightaligned with the reference PRB 1406 for the default numerology. Thus, ifthe reference PRBs of different numerologies are right aligned with thereference PRB of the default numerology, then the highest frequency ofeach reference PRB are aligned with the highest frequency of thereference PRB 1406 of the default numerology as shown in FIG. 14. Thus,reference PRBs 1402, 1404, 1406, 1408 are right aligned.

In option Alt (ii)-3, for any SCS 2^(n)f₀, with n≥1, if n is odd, thereference PRB of 2^(n-1)f₀ is right-aligned with the reference PRB ofSCS 2^(n)f₀. If n is even, the reference PRB of 2^(n-1)f₀ isleft-aligned with the reference PRB of SCS 2^(n)f₀.

In option Alt (ii)-4, for any SCS 2^(n)f₀, with n≥1, if n is odd, thereference PRB of 2^(n-1)f₀ is left-aligned with the reference PRB of SCS2^(n)f₀. If n is even, the reference PRB of 2^(n-1)f₀ is right-alignedwith the reference PRB of SCS 2^(n)f₀.

FIG. 15 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=2^(n) for SCS 0.5f₀ and option Alt (ii)-4 for SCS 2f₀ and 4f₀. Thereference PRB 1504 for SCS 2f₀ is left aligned with the reference PRB1506 for the default numerology. The reference PRB 1502 for SCS 4f₀ isright aligned with the reference PRB 1504 for SCS 2f₀. The reference PRB1508 for SCS 0.5f₀ is right aligned with the reference PRB 1506 for thedefault numerology.

FIG. 16 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-2 for SCS 2f₀ and 4f₀. Thereference PRB 1604 for SCS 2f₀ is right aligned with the reference PRB1606 for the default numerology. The reference PRB 1602 for SCS 4f₀ isright aligned with the reference PRB 1604 for SCS 2f₀. The reference PRB1608 for SCS 0.5f₀ is left aligned with the reference PRB 1606 for thedefault numerology.

FIG. 17 is a diagram that illustrates the location of the reference PRBsfor multiple different numerologies according to alternative A withk_(n)=1 for SCS 0.5f₀ and option Alt (ii)-3 for SCS 2f₀ and 4f₀. Thereference PRB 1704 for SCS 2f₀ is right aligned with the reference PRB1706 for the default numerology. The reference PRB 1702 for SCS 4f₀ isleft aligned with the reference PRB 1704 for SCS 2f₀. The reference PRB1708 for SCS 0.5f₀ is left aligned with the reference PRB 1706 for thedefault numerology.

In the preceding examples, a frequency range of the reference PRB of anynumerology is a superset of a frequency range of the reference PRB ofeach numerology having a smaller subcarrier spacing (SCS).

FIG. 18 is a diagram of a graph 1800 illustrating an example ofreference PRB for mixed numerologies.

FIG. 19 is a diagram of a graph 1900 of an example frequency locationindexing in the case of mixed numerologies which are multiplexed infrequency domain (FDMed mixed numerologies).

FIG. 20 is a flowchart of an embodiment of a method 2100 for determininga frequency location indexing in wideband CC. The method 2000 begins atblock 2002 where the UE obtains a UE independent frequency referencepoint. The UE may obtain the UE independent frequency reference pointusing, for example, any of the methods discussed and described above. Atblock 2004, the UE determines a UE independent frequency location indexof a frequency location for a UE specific PRB, reference signal, orother UE specific signal according to the UE independent frequencyreference point.

It should be appreciated that one or more steps of the embodimentmethods provided herein may be performed by corresponding units ormodules, according to FIG. 21. For example, a signal may be transmittedby a transmitting unit or a transmitting module. A signal may bereceived by a receiving unit or a receiving module. A signal may beprocessed by a processing unit or a processing module. Other steps maybe performed by UE independent frequency reference point obtainingmodule and a UE frequency location index determining module. Therespective units/modules may be hardware, software, or a combinationthereof. For instance, one or more of the units/modules may be anintegrated circuit, such as field programmable gate arrays (FPGAs) orapplication-specific integrated circuits (ASICs). It will be appreciatedthat where the modules are software, they may be retrieved by aprocessor, in whole or part as needed, individually or together forprocessing, in single or multiple instances as required, and that themodules themselves may include instructions for further deployment andinstantiation.

Additional details regarding the EDs 110 and the base stations 170 areknown to those of skill in the art. As such, these details are omittedhere for clarity.

While several embodiments have been provided in the present disclosure,it should be understood that the disclosed systems and methods might beembodied in many other specific forms without departing from the spiritor scope of the present disclosure. The present examples are to beconsidered as illustrative and not restrictive, and the intention is notto be limited to the details given herein. For example, the variouselements or components may be combined or integrated in another systemor certain features may be omitted, or not implemented.

In addition, techniques, systems, subsystems, and methods described andillustrated in the various embodiments as discrete or separate may becombined or integrated with other systems, modules, techniques, ormethods without departing from the scope of the present disclosure.Other items shown or discussed as coupled or directly coupled orcommunicating with each other may be indirectly coupled or communicatingthrough some interface, device, or intermediate component whetherelectrically, mechanically, or otherwise. Other examples of changes,substitutions, and alterations are ascertainable by one skilled in theart and could be made without departing from the spirit and scopedisclosed herein.

What is claimed is:
 1. A method for physical resource block (PRB)indexing in a user equipment (UE) in a carrier, comprising: obtaining,at the UE, a UE-independent frequency reference point; and determining,by the UE, a UE-independent PRB index of a PRB according to theUE-independent frequency reference point, wherein the UE-independentfrequency reference point is identified by a specific PRB with respectto a reference synchronization signal block (SSB), the carrier comprisesa first numerology and a second numerology, and a first UE-independentfrequency reference PRB of the first numerology is left-aligned with asecond UE-independent frequency reference PRB of the second numerologyat the UE-independent frequency reference point.
 2. The method of claim1, wherein the specific PRB is obtained by an offset from a lowestfrequency of the SSB.
 3. The method of claim 2, wherein the offset isfrom a center frequency of the carrier to the UE-independent frequencyreference point.
 4. The method of claim 1, wherein the UE-independentfrequency reference point is a single frequency reference point for PRBindexing for reference signal generation by all UEs in the carrier. 5.The method of claim 1, wherein if a first subcarrier spacing of thefirst numerology is a 2n multiple of a second subcarrier spacing of thesecond numerology, a first frequency size of the first UE-independentfrequency reference PRB of the first numerology is a 2n multiple of asecond frequency size of the second UE-independent frequency referencePRB of the second numerology.
 6. The method of claim 1, wherein theUE-independent frequency reference point is the first UE-independentfrequency reference PRB and the UE-independent PRB index is a firstindex, and before obtaining the first UE-independent frequency referencePRB, the method further comprises: obtaining a second frequencyreference point; and determining a second index of another PRB accordingto the second frequency reference point, the another PRB for decoding aremaining minimum system information (RMSI) or a control resource set(CORESET) of the RMSI.
 7. A method for physical resource block (PRB)indexing in a base station, comprising: transmitting, to a userequipment (UE) in a carrier, a UE-independent frequency reference point,wherein the UE-independent frequency reference point is for determininga UE-independent PRB index of a PRB, and the UE-independent frequencyreference point is identified by a specific PRB with respect to areference synchronization signal block (SSB), the carrier comprises afirst numerology and a second numerology, and a first UE-independentfrequency reference PRB of the first numerology is left-aligned with asecond UE-independent frequency reference PRB of the second numerologyat the UE-independent frequency reference point.
 8. The method of claim7, wherein the specific PRB is obtained by an offset from a lowestfrequency of the SSB.
 9. The method of claim 7, wherein theUE-independent frequency reference point is a single frequency referencepoint for PRB indexing for reference signal generation by all UEs in thecarrier.
 10. The method of claim 7, wherein if a first subcarrierspacing of the first numerology is a 2n multiple of a second subcarrierspacing of the second numerology, a first frequency size of the firstUE-independent frequency reference PRB of the first numerology is a 2nmultiple of a second frequency size of the second UE-independentfrequency reference PRB of the second numerology.
 11. A user equipment(UE) in a carrier, the UE comprising: a non-transitory memory storagecomprising instructions; and one or more processors in communicationwith the non-transitory memory storage, wherein the one or moreprocessors execute instructions for: obtaining a UE-independentfrequency reference point; and determining a UE-independent physicalresource block (PRB) index of a PRB according to the UE-independentfrequency reference point, wherein the UE-independent frequencyreference point is identified by a specific PRB with respect to areference synchronization signal block (SSB), the carrier comprises afirst numerology and a second numerology, and a first UE-independentfrequency reference PRB of the first numerology is left-aligned with asecond UE-independent frequency reference PRB of the second numerologyat the UE-independent frequency reference point.
 12. The UE of claim 11,wherein the specific PRB is obtained by an offset from a lowestfrequency of the SSB.
 13. The UE of claim 12, wherein the offset is froma center frequency of the carrier to the UE-independent frequencyreference point.
 14. The UE of claim 11, wherein the UE-independentfrequency reference point is a single frequency reference point for PRBindexing for reference signal generation by all UEs in the carrier. 15.The UE of claim 11, wherein if a first subcarrier spacing of the firstnumerology is a 2n multiple of a second subcarrier spacing of the secondnumerology, a first frequency size of the first UE-independent frequencyreference PRB of the first numerology is a 2n multiple of a secondfrequency size of the second UE-independent frequency reference PRB ofthe second numerology.
 16. The UE of claim 11, wherein theUE-independent frequency reference point is the first UE-independentfrequency reference PRB and the UE-independent PRB index is a firstindex, and before obtaining the first UE-independent frequency referencePRB, the one or more processors further execute instructions for:obtaining a second frequency reference point; and determining a secondindex of another PRB according to the second frequency reference point,the another PRB for decoding a remaining minimum system information(RMSI) or a control resource set (CORESET) of the RMSI.
 17. A basestation comprising: a non-transitory memory storage comprisinginstructions; and one or more processors in communication with thenon-transitory memory storage, wherein the one or more processorsexecute instructions for: transmitting, to a user equipment (UE) in acarrier, a UE-independent frequency reference point, wherein theUE-independent frequency reference point is for determining aUE-independent physical resource block (PRB) index of a PRB, and theUE-independent frequency reference point is identified by a specific PRBwith respect to a reference synchronization signal block (SSB), thecarrier comprises a first numerology and a second numerology, and afirst UE-independent frequency reference PRB of the first numerology isleft-aligned with a second UE-independent frequency reference PRB of thesecond numerology at the UE-independent frequency reference point. 18.The base station of claim 17, wherein the specific PRB is obtained by anoffset from a lowest frequency of the SSB.
 19. The base station of claim17, wherein the UE-independent frequency reference point is a singlefrequency reference point for PRB indexing for reference signalgeneration by all UEs in the carrier.
 20. The base station of claim 17,wherein if a first subcarrier spacing of the first numerology is a 2nmultiple of a second subcarrier spacing of the second numerology, afirst frequency size of the first UE-independent frequency reference PRBof the first numerology is a 2n multiple of a second frequency size ofthe second UE-independent frequency reference PRB of the secondnumerology.